Automatic stoker



June 24, 1930. A. o. DADY AUTOMATIC sToKER Fld Feb. 6, 1929 2Sheets-Shuk l June 24, 1930. A. o. DADY AUTOMATIC STOKER 2 Sheets-Sheet2 Filed Feb. 6, 1929 EN x5 Patented June 24, 1930 i UNITEDY STATES :Li.. F ,una

ARTHUR O. DADY, OF PORTLAND, OREGON AUTOMATIC STOKER Application ledFebruary 6, 1929. Serial No. 337,951.

My invention relates to underfeed automatic furnace stokers for feedingsolid fuel .to furnaces, and of the type comprising a hopper, the lowerpart of which constitutes a ram-chamber in which a ram is operated by asuitable mechanical power, thereby to move the fuel into the retort ofthe furnace.

One of the objects of my invention is to promote the feeding of the fuelfrom the hopper to the retort by moving the fuel down an inclined way;to employ in connection with such inclined way a fuel moving element,that is, a pusher, and further to move this pusher along a horizontalguide wa)T instead of along the floor of the inclined way. And since thepusher is conveniently constructed of a pusher rod carrying one or morepusher heads, a further object of my invention is to arrange the guideway for the pusher so that in the retracting movement of the pusher, aslthe pusher head nearest the ram-chamber approaches the lat- 'ter thepusher head shall disappear in the guide way, that is to sa droprelatively below the surface of the atter.

By so doing the pusher head can be more effectively brought under a massof fuel to be moved forward, and the movement of such la mass into theretort of the furnace is fa- Cilitated. 1

Al further object of my invention is to prevent the clogging or chokingof the outlet opening from the ram-chamber of the hopper to thepassageway of the retort of the furnace by chunks of fuel becominglodged in such outlet opening which are too large to pass through.

To this end I provide a fuel crushing element about such outlet openingwith which the ram cooperates in its forward movement, thus breakingdown any packing of large chunks of the fuel which otherwise wouldobstruct the feeding of the fuel forward to vthe retort of the furnace.p

" The above described features of my invention and other incidentalfeatures are hereinafter fully described with reference to theaccompanying drawings; in which Fig. 1 is a longitudinalverticalfsection of Fig. 2.

a stoker mechanism of the character described embodying my invention;

Fig. 2 is an enlarged detail longitudinal section of the feeding end ofthe mechanism. Y

Fig. 3 is a detail transverse section on line 3 3, Fig. 2.

Fig. 4 is a similar section on line 4 4,-

Fig. 5 is a similar section on line 5 5, Fig. 2.

Fig. 6 is a similar section on line 6 6, Fig. 2.

Fig. 7 is a perspective side elevation of the pusher element of myinvention including the means for connecting such pusher element withthe ram ;v

Fig. 8 is a perspective det-ail of one of the pusher heads carried bythe pusher element;

Fig. 9 is a top view corresponding with Fig. 1 with parts broken away;and

Fig. 10 is a left end view of the fuel tunnel section of my stokermechanism, taken on the line 10-10 of Fig. 1.

Referring now to the drawings,.my auto-Y matic Stoker comprises a hoppera opening at its bottom into a semi-cylindrical ram-chamber b in which aram c is operated b means of a fluid under pressure, such as oil, fromany suitable source as a pump, not shown. The ram c is operativelyconnectedv by a piston rod g with the piston e which vhas movement inthe closed piston chamber of a stationary housing h. In lon itudinallyaligned relation with the ram chamber 3, aforesaid.

In'the present construction the alternate inlet and outlet of motiveiluid into and .from the respective ends of the piston connected to therear end of said piston chamber by a pipe connection or passage 5.

Centrally between' 'the openings of the pipe connections 4 and 5 intosaid valve chamber an-outlet port or passage 6 :is formed and is adaptedfor alternate communication with the pipe connections 4 and 5, with suchalternate communication with the outlet passage 6 controlled by thehereinafter described slide valve 11 moving in, said valve chamber. Saidoutlet port or passage 6 has pipe connection 3a with the fluid inlettothe pump employed to maintain a supply of motivefluid under pressurefor operation of the mechanism.

The supply of motive fluid is introduced into the valve chamber of saidmechanism by a pipe connection 10*l and branch passages 10, asillustrated in Fig. 2.

The sliding valve 11 above referred to,is preferably of the piston typeshown and is formed with a central peripheral recess or chamber adaptedfor alternate registry of the aforesaid central outlet passage 6 withthe passages 4 and 5 of the piston chamber, and so that when the passage4 is in communication with motive fluid under pressure in the valvechamber, the other passage 5 will be in communication with the outletpassage 6, and vice versa. d.

At one end theY valve 11 carries an operating stem 12, extending throughthe wall of the valve chamber, and provided at a point exterior to saidwall with a pair of collars or tappet 12a and 12b in properly spacedrelation, as shown in Figs. 1 and2, and adapted for alternate operativeengagement by a tappet sleeve or lug 13a of a depending bracket 13secured on the inner end` of the ram c aforesaid. p

In the above described arrangement of parts, the valve 1 1 being in theposition shown in Fig. 2, motive fluid supplied to the valve chamberthrough passages 10, 10a passes through the pipe or passage 5 to therear end of the piston chamber, to drive the piston e and ram c inaforward direction,

while the fluid in the forward end of the piston chamber passes throughthe pipe or passage 4 into the central chamber'of the slide valve 11 andthence through the outlet port of passage 6 aforesaid. The forwardmovement of the piston e continues until the tappet 13a carried by theram c contacts with the collar 12b of the valve stem 12-,and moves thevalve 11 into its forward position. With the attainment' of such forwardosition of the valve 11, the connections o the ports and passages abovedescribed are rey versed, and a rearward movement of the ram c andpiston e takes place, as-usual in the present type of reciprocatingmotors.

An outwardly flaring fuel tunnel 17 is provided leading from the fuelopening 18 1n the ram-chamber into the combustion Matrose chamber p,which is also provided witha longitudinal groove 17a, the bottom ofwhich is horizontal and forms a guide for the pusher rod 15. The pusherrod 15 is constructed in removable segments 15, so that it may be madeof any desirable length and is provided with spaced pusher heads 20formed with concaved sloping faces 20a vand abrupt forward end 20", seeFigs. 7 and 8.l

By this construction the pusher heads 20 are moved forward as the ram ismoved and are retracted as the ram is retracted and the pusher headadjacent thev fuel tunnel is retracted into the groove 17a out of theway of the fuel. Thus the pusher head 20 serves to move the fuel forwardin advance of the ram c to distribute it evenly about the combustionchamber p. Further the retraction of the pusher heads serves to disturband break up any coking or caking of the fuel tok prevent the formationof clinkers and the li e.

The fuel opening 18 in the ram-chamber is provided about thecircumference of its face with radial teeth or projections 25, see Fig.4, against which largechunks of fuel will be crushed by the forwardmovement of the ram.

The fuel opening 18 is also so arranged relative to the ram-chamber 5band the bottom of the hopper a.' that its center is well above thebottom of the hopper and the sides do not form the sides of the fuelopening so that there is no tendency for the fuel in the hopper to -archover the ram and not fall before it, as would be the case were the' fuelsupported at each side of the fuel opening by the walls of the saidhopper.

I claim: 1. In an automatic stoking device for furnaces, a retort, afuel hopper including in Vits lower part a ram-chamber, a fuel-tunnelconnecting said chamber with. the retort of the furnace, said tunnelhavlng asloping oor provided with a horizontal longitudi-` its lowerpart a ram-chamber, a' fuel-tunnelA connecting said chamber with theretort ofv the furnace, said tunnel having a sloping floor provided witha horizontal lon itudinal grove lying in a plane below the oor of theram-chamber, a ram reciprocated in said ram-chamber, a pusher rodconnected to said ram, a pusher head carried by said pusher rod and saidpusher rod and said head thereof sliding in said ioor groove.

3. In an automatic stolcing device for furnaces, a retort, a fuel hopperincluding in its lower part a ram-chamber, a fuel tunnel connecting saidchamber with the retort of the furnace, said tunnel having a slopingfloor provided with a horizontal longitudinal groove lying in a planebelow the floor of the ram-chamber and increasing in depth towards thelatter, a ram reciprocated in said ram-chamber, a pusher rod connectedto said ram, a' pusher head carried by said pusher rod, and said pusherrod and said head thereof sliding in said floor groove thepusher-headin'one movement partly disappearing in said groove.

4. In an automatic stoking device for furnaces, aretort, a fuel hopperincluding in its lower part a ram-chamber, a fuel tunnel connecting saidchamber with the retort of the furnace, said tunnel having a vertical Ytapering enlargement from said ram-chamber to said retort including aslopin of the tunnel provided with a horizontal longitudinal groovelying in a plane below the floor of the ram-chamber, a ramVreciprovcated in lsaid ram-chamber, a pusher rod connected to said ram,apusher head carried by said pusher rod, and said pusher rod and saidheadv thereof sliding in said floor groove. 5. In an automatic stokingdevice for furnaces, a retort, a fuel hopper including in its lower parta ram-chamber, a fuel tunnel connecting said chamber withthe retort ofthe furnace, said tunnel having a sloping floor provided with ahorizontal longitudinal groove lying in a plane below the floor of theram-chamber, and increasing in depth towards the` latter, a ramreciprocated in said'ram-chamber, a, pusher rod connected to said ram, awedgeshaped pusher head carried by said pusher rod, the edge of thewedge pointed towards .the ram-chamber, and said pusher rod and saidhead thereof sliding in said ioor groove the pusher head in one movementpartly disappearing in said groove.

6. In an automatic stoking device for furnaces, a retort, a fuel hopperincluding in its lower part a ram-chamber, a fuel tunnel connecting saidchamber with the retort of the furnace, said tunnel having-a slopingfloor provided with a horizontal longitudinal groove lying in a planebelow the floor of the ram-chamber, a ram reciprocated in` saidram-chamber, said ram provided with an arm extending through an' openingin the Hoor of the ramchamber,a pusher rod connected to said arm andoperated under the floor of the ram chamber, a pusher head carried bysaid pusher rod, said pusher rod and said head thereof sliding in saidfloor groove, and a hydraulic engine connected to said ram, and a valvecontrolling saideny gine connected to said ram ar'rn. v

7. In an automatic stoking device for furnaces, a retort, a fuel hopper'including in its lower part a ram-chamber, a fuel tunnel connectingsaid chamber withY the retort of the furnace, said tunnel having asloping door provided with a horizontal longitudinal groove lying in aplane below the floor of the ram-chamber, and increasing in depthtowards the latter, a ram reciprocated in said ram-chamber, said ramprovided with an arm extending through an opening in the floor of theram-chamber, a pusher rod connected to said arm and operated under thefloor of the ram chamber, a pusher head. carried by said pusher rod, andsaid pusher rod and said head thereof sliding in said Hoor groove thepusher head in one movement more or less disappearing in said groove.

8. In an automatic stoking device for furnaces, a retort, a fuel hopperincluding in its lower part a ram-chamber, a fuel tunnel connecting saidchamber with the retort of the furnace, said tunnel having a slopingfloor provided with a horizontal longitudinal groove lying in a planebelow the Hoor of the ram-chamber, and increasing in depth towards thelatter, a ram reciprocated in' said ram-chamber, said ram provided withan arm extending through an opening in the Hoor of the ram-chamber, apusher rod connected to said arm and operated under thev door of therain chamber, a wedge-shaped pusher head carried by said pusher rod, theedge of the wedge pointed towards the ramchamber, and sa1d pusher rodand said head thereof sliding in said door groove the pusher head in onemovement more or less disappearing lin said groove.

9. n an automatic stoking device for furnaces, a retort, a fuel hopperincluding in its lower part a ram-chamber, Va fuel tunnel connectingsaid-chamber with the retort of the furnace, said tunnel having asloping floor provided with a horizontal longitudinal groove lying in aplane below the floor of the ram-chamber, aram recipro cated in saidram-chamber, a pusher rod operatively connected to said ram and havingmovement in the longitudinalJ groove of the sloping floor of saidtunnel, and the wall of the ram chamber having the outlet opening tosaid tunnel provided within the ram-chamber with fuel crushingprotubeances disposed concentrically about said openinlg.

10. n an automatic stoking device for furnaces, a retort, a fuel hopperincluding in its lower part a ram-chamber, a fuel 'below the floor ofthe ram-chamber, and increasing in depth towards the latter, a ram 4Weense reciprocated in said ram-chamber, said ram provided with an armextending through an opening in the floor of the ram-chamber, a pusherrod connected (to said arm and operated under the oor of the ramchamber, a Wedge-shaped pusher head carried by said J pusher rod, theedge of thevwedge pointed towards the ram-chamber, said pusher rod andsaid head thereof sliding in said `door groove the pusher head in onemovement partly disappearing in said groove, and means for reciprocatingsaid rem.;

ARTHUR DADY.

